In addition to their influences upon digestive and nutritive processes, the major nasal chemosensory systems of man (the olfactory and trigeminal nerves) play a significant role in monitoring the intake of air-bound substances into the respiratory system. Many studies have suggested that the sensitivity of women to a number of odorants fluctuates during the menstrual cycle. Such fluctuations have been believed to depend, to a large extent, upon endocrinological factors. However, previous studies of this phenomenon have failed to (a) utilize psychophysical procedures whose sensitivity measures are not confounded by response biases, and (b) establish whether or not a correlation exists between blood levels of particular reproductive hormones of interest and sensory sensitivity -- a correlation critical for the evaluation of such beliefs. The proposed research will utilize signal detection theory to obtain measures of nasal chemosensory sensitivity during various phases of the menstrual cycle of women with and without (i.e., general "anosmics" CN#1 function. Signal detection procedures provide a measure of perceptual sensitivity that is independent of response biases. Concomitant measurement of circulating levels of LH, FSH, estradiol and progesterone by modern radioimmunoassay procedures will allow for a direct test of the hypothesis that relative levels of circulating hormones are directly related to intranasal chemosensory sensitivity and/or placement of response criteria.